What are Biofertilisers ? Write a brief note on them.

Explanation

Organisms that enrich the nutrient quality of the soil are called Biofertilisers
E.g.: Bacteria, fungi and Cyanobacteria.
(1). Bacteria: In symbiotic Bacteria, Rhizobium is present in the root nodules and legumes. These bacteria fix atmospheric nitrogen into organic forms which is used by the plant as a nutrient. other bacteria can fix atmospheric nitrogen, while free living in the soil are Azospirillum and Azotobacter thus enriching the nitrogen content of the soil.
(2). Fungi : The symbiotic, association between fungal members and roots of vascular plants is called mycorrhiza. many members of the genus Glomus forms Mycorrhiza. the fungal symbiont in these associations facilitates absorption of phosphorous by the plant from the soil. plants having such associations show resistance to root-borne pathogens, tolerance to salinity and drought and an overall increase in plant growth and development.